adding migration check for sandbox clone

util/jenkins/check-migrations.sh

 #!/usr/bin/env bash
 set -x
 
-if [[
-        -z $WORKSPACE       ||
-        -z $environment     ||
-        -z $deployment
-    ]]; then
+if [[ -z $WORKSPACE ]]; then
     echo "Environment incorrect for this wrapper script"
     env
     exit 1
@@ -13,7 +9,7 @@ fi
 
 
 env
-cd $WORKSPACE/edx-platform
+cd "$WORKSPACE/edx-platform"
 
 # install requirements
 # These requirements will be installed into the shinginpanda
@@ -27,7 +23,7 @@ pip install --exists-action w -r requirements/edx/repo.txt
 pip install --exists-action w -r requirements/edx/github.txt
 pip install --exists-action w -r requirements/edx/local.txt
 
-cd $WORKSPACE/configuration/playbooks/edx-east
+cd "$WORKSPACE/configuration/playbooks/edx-east"
 
 if [[ -f ${WORKSPACE}/configuration-secure/ansible/vars/${deployment}.yml ]]; then
     extra_var_args+=" -e@${WORKSPACE}/configuration-secure/ansible/vars/${deployment}.yml"
@@ -40,7 +36,14 @@ if [[ $db_dry_run == "false" ]]; then
     extra_var_args+=" -e db_dry_run=''"
 fi
 
-extra_var_args+=" -e@${WORKSPACE}/configuration-secure/ansible/vars/${environment}-${deployment}.yml"
+if [[ -f ${WORKSPACE}/configuration-secure/ansible/vars/${environment}-${deployment}.yml ]]; then
+    extra_var_args+=" -e@${WORKSPACE}/configuration-secure/ansible/vars/${environment}-${deployment}.yml"
+fi
+
+for extra_var in $extra_vars; do
+    extra_var_args+=" -e@${WORKSPACE}/configuration-secure/ansible/vars/$extra_var"
+done
+
 extra_var_args+=" -e edxapp_app_dir=${WORKSPACE}"
 extra_var_args+=" -e edxapp_code_dir=${WORKSPACE}/edx-platform"
 extra_var_args+=" -e edxapp_user=jenkins"